Embodiments of the inventive concepts described herein relate to an electrode device, and more particularly, to an electrode device capable of measuring a living body signal with a simple electrode structure and transmitting electrical signals obtained from a living body without loss.
A body may be a type of a conductor and a large amount of micro-current may occur in the body. Accordingly, characteristics in the body are measured based on a result of detecting the micro-current from the body or detecting a change in a current on external stimulation. In general, the above-described manner is used to measure electrocardiogram (ECG), electromyogram (EMG), electroencephalogram (EEG), skin resistance (e.g., galvanic skin response (GSR)), eyeball exercise (e.g., an electrooculogram (EOG)), body temperature, pulse rate, blood pressure, body movements, and the like, and an electrode for a living body is used to detect a change in a living body signal.
This electrode includes an electrode member which is formed of a conductive material and is disposed so as to be usually exposed to an outside. In addition, a sheet member includes an adhesive surface to allow the electrode member to adhere to a skin of the body and is disposed around the electrode member, and a snap projection is disposed on the electrode member so as to penetrate the sheet member and upwardly protrude. The snap projection is connected to a socket of a connection wire part connected to a signal processing module of a living body signal analysis device. Furthermore, an adhesive material of a gel state such as electrolyte is coated on the electrode member exposed to the outside to allow a contact with the skin to be maintained stably, and the relatively stable contact between the skin and the electrode member is maintained through the coated adhesive material.
However, the skin contains an outer skin layer including a horny layer of a skin barrier function, which prevents moisture, electrolyte, and the like from being outputted into an outside of the body and foreign substance from being inputted from the outside. For this reason, biological signals, such as the amount of current or a change in a current caused in a body part to be measured, are subjected to interference by a skin layer while passing through the skin layer, and thus, the biological signals are weakened or a noise occurs.
Accordingly, even though the adhesive material is interposed between the electrode member and the skin, a conventional electrode measures a signal generated from an outer skin layer upon measuring, thereby making it difficult to completely measure a living body signal generated in the body part as it is. In addition, the adhesive material, used to maintain a stable contact and to improve signal transmission between the electrode member and the skin, causes skin irritation even though an individual difference is when being in contact with the skin.